DIGESTION OF THE ALBUMINS. 175 



The material which is exposed to the action of the pancreatic 

 juice consists in part of the primary albumoses which were formed 

 In the stomach, in part of Kiilme's anti-albumid, and in part of 

 syntonin and of native albumins, in soluble or insoluble form, which 

 have escaped the action of the gastric juice. The latter are first 

 dissolved, and together with the syntonins transformed into alkaline 

 albuminate. This result, analogous to the formation of the syntonin 

 in acid solution, as well as the further decomposition of the alkaline 

 albuminate, is no doubt primarily referable to the action of the 

 alkalies of the pancreatic juice, and merely hastened by the ferment 

 which is at the same time present. But unlike the action of the 

 gastric juice, tryptic digestion immediately leads to the formation of 

 deutero-albumoses without the intermediary production of primary 

 albumoses in the sense of Kiihne. According to older views, 

 amphopeptone then results. Subsequently the anti- and the hemi- 

 groups become separated with the formation of antipeptone and 

 hemipeptone, respectively. Hemipeptone, however, is manifestly 

 only a hypothetical substance, as, in experiments in vitro at least, 

 no substance of this character can be obtained. Instead we find 

 amido-acids, tryptophan, and other substances, which are as yet 

 imperfectly known whenever the process of digestion has extended 

 beyond the formation of deutero-albumoses. In the living organ- 

 isms, it is true, these products are found only in traces, and we 

 might hence imagine that hemipeptone is here resorbed as soon as 

 formed. But beyond the absence of amido-acids as just stated, we 

 have no actual proof of such an occurrence. 



Antipeptone, on the other hand, viz., a substance or substances 

 which still give the biuret reaction, but which, in contradistinction 

 to the albumoses, cannot be precipitated by salting with ammonium 

 sulphate, can always be obtained in experiments in vitro. As 

 regards the chemical nature of the antipeptone, however, opinions 

 differ. Kiihne and Chittenden long ago questioned the chemical 

 unity of the body, and Kutscher has recently announced that he 

 was able to isolate the three known hexon bases, as also small 

 amounts of leucin, tyrosin, and asparaginic acid from the substance. 

 In addition, still other products of digestion were found, which 

 were not identified, however. In my own laboratory I have 

 attempted to repeat Kutscher's work, together with Dr. Amberg, 

 and we have found that, as a matter of fact, Kiihne's antipeptone 

 does not represent a chemical unity, but owing to Kutscher's insuffi- 

 cient working directions we were unable to confirm his results in 

 detail. It manifestly consists of two portions however, one of which 

 can be precipitated with phosphotungstic acid. This portion repre- 

 sents about 30 per cent, of Kiihne's antipeptone, and according to 

 Kutscher consists to the extent of 30-31 per cent, of hexon bases. 

 Siegfried's claim that antipeptone is identical with his carnic acid, 

 and may be represented by the formula C 10 H 15 N 3 O 5 , is, in view of 

 Kutscher's work and my own experience, altogether untenable. 



